1. Field of the Invention
This invention relates to a polarizing microscope which permits orthoscopic observation and conoscopic observation to be effected, and in particular to a polarizing microscope which permits the both observations to be effected in the same field of view at a time.
2. Description of the Prior Art
A polarizing microscope generally comprises a so-called orthoscopic system in which the polarizer of a polarizing plate is disposed forwardly of a condenser and the analyzer of the polarizing plate is disposed on the optical axis between an objective lens and an eyepiece, and a so-called conoscopic system in which a Bertrand's lens (an image forming lens ) is inserted between the objective lens on the optical axis and the eye-piece to cause the exit pupil (rearward focal plane) of the objective lens to be imaged on the forward focal plane of the eye-piece. Accordingly, both the orthoscopic observation in which the image of a sample formed by the objective lens is observed through the eye-piece and the conoscopic observation in which an interference image created on the exit pupil (rearward focal plane) of the objective lens is observed through the Bertrand's lens and the eye-piece are made possible by these two optical systems.
However, the conventional polarizing microscope is designed such that the orthoscopic observation and the conoscopic observation are effected independently of each other and therefore, in order that to what region of the sample the interference image observed by means of the conoscopic system belongs may be confirmed, it has been necessary to retract the Bertrand's lens from the optical axis and change over the observation to the orthoscopic observation, and further change over the condenser to one of narrow field of view if the illumination is of a wide field of view. Therefore, cumbersome operation has been required for conoscopically observe the interference images of many regions of the sample, and quick observation has been impossible.